Make your infused gin as far ahead as you can. Add all of the ingredients, except for the gin, to a small pan. Gently bring the mixture to the boil then simmer over a low heat for 8–10 minutes, until it forms a light syrup. Take off the heat and leave to cool.
Once cold, pour the the cooled syrup and its infusions into a glass bottle and top up with the gin. Shake well to mix and store for at least a week to infuse. Strain before using.
To make your cocktails, divide a handful of ice cubes between two old fashioned whisky glasses. Mix the ingredients in a jug, stir well and divide between the glasses.